Re: dangerously dedicated physical disks.
>Thank you very much about your efforts to explain me in detailed the >'dangerous dedicated' term. > >Regards, > >atar. And as a complete newb trying to wrestle with some of the concepts here, may I add my thanks here for clarifying yet another well-understood matter which leaves us floundering. Thanks again to all who have diffused some of the mystique which surrounds BSD from time to time. ++ Graham Todd signature.asc Description: PGP signature
Re: dangerously dedicated physical disks.
On Mon, 23 Sep 2013, Robert Simmons wrote: On Mon, Sep 23, 2013 at 6:25 AM, Polytropon wrote: With GPT, there is no reason to use BSD disklabels at all. And most modern computers do not have any problem booting it. The old MBR approach (as well as dedicated) will probably only be needed in niche applications and exceptions. You can have all the advantages of "being easy stuff" known from dedicated layout by using the GPT tools, plus you gain "more compatibility" if this matters. Not entirely. Due to GEOM specs, if you create a GELI encrypted container, you cannot use GPT partitioning inside that container. You must use BSD. This is an edge case, and I've submitted a bug about it a while ago, but like I just said, this is apparently a feature not a bug. It's not GEOM, it's just GPT. By specification, the backup partition table has to be at the end of the disk. That interferes with anything else that wants to put metadata there, like GELI or gmirror. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated physical disks.
On Mon, Sep 23, 2013 at 6:25 AM, Polytropon wrote: >> With GPT, there is no reason to use BSD disklabels at all. > > And most modern computers do not have any problem booting it. > The old MBR approach (as well as dedicated) will probably only > be needed in niche applications and exceptions. You can have > all the advantages of "being easy stuff" known from dedicated > layout by using the GPT tools, plus you gain "more compatibility" > if this matters. Not entirely. Due to GEOM specs, if you create a GELI encrypted container, you cannot use GPT partitioning inside that container. You must use BSD. This is an edge case, and I've submitted a bug about it a while ago, but like I just said, this is apparently a feature not a bug. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated physical disks.
On Sun, 22 Sep 2013 08:25:24 -0600 (MDT), Warren Block wrote: > It's "dangerous" because that partitioning format is rare outside of > BSD-based systems. Disk utilities may not recognize it, and could > damage it. I think this is a good characterization of the term currently used. In historical context this layout would deserve the name "traditional", as non-PC BSD installations did not _require_ a MBR "enclosing" to be present - this is a concept introduced by the PC world. Most PCs still work with "dedicated" perfectly well if desired (even though there is no real reason to use that layout approach). I try to avoid the part "dangerously" because the danger is only significant in non-BSD land, like some obscure systems that could try to "repair" something and cause data loss, which is well known and feared... :-) > Most of the rest of the world used MBR partitioning, which allowed up to > four MBR partitions (called "slices" by FreeBSD) per disk. Those are, precisely called "DOS primary partitions" (in difference to "DOS extended partitions" which somehow behave like slices in BSD terminology). :-) > Yes, one partition format inside another. It only seems complicated > because it is. Which makes it useful and flexible. :-) > With GPT, there is no reason to use BSD disklabels at all. And most modern computers do not have any problem booting it. The old MBR approach (as well as dedicated) will probably only be needed in niche applications and exceptions. You can have all the advantages of "being easy stuff" known from dedicated layout by using the GPT tools, plus you gain "more compatibility" if this matters. -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated physical disks.
Thank you very much about your efforts to explain me in detailed the
'dangerous dedicated' term.
Regards,
atar.
Warren Block wrote:
On Sun, 22 Sep 2013, atar wrote:
During the reading of the FreeBSD handbook, I've encountered at the
term 'dangerously dedicated' regarding physical disks and the author of
this chapter in the FreeBSD handbook didn't think this term need more
clarity. so for newbies like me in the FreeBSD world I want to ask:
what's the 'dangerously dedicated' term meaning by?
The term refers to a disk partitioned with only the BSD disklabel
partition table:
disk ada0
partition "a" (ada0a, /)
partition "b" (ada0b, swap)
partition "d" (ada0d, /var)
partition "e" (ada0e, /tmp)
partition "f" (ada0f, /usr)
It's "dangerous" because that partitioning format is rare outside of
BSD-based systems. Disk utilities may not recognize it, and could
damage it.
Most of the rest of the world used MBR partitioning, which allowed up to
four MBR partitions (called "slices" by FreeBSD) per disk.
Since four slices is not enough for the standard FreeBSD disk layout,
with /, swap, /var, /tmp, and /usr, the standard procedure is to use MBR
partitioning, with the MBR partitions ("slices") being sub-partitioned
by a BSD disklabel.
disk ada0
MBR slice 1 (ada0s1)
partition "a" (ada0s1a, /)
partition "b" (ada0s1b, swap)
partition "d" (ada0s1d, /var)
partition "e" (ada0s1e, /tmp)
partition "f" (ada0s1f, /usr)
MBR slice 2 (ada0s2)
...
Yes, one partition format inside another. It only seems complicated
because it is.
GPT is the new partitioning format, which makes things much simpler by
being capable of up to 128 partitions in the standard configuration.
With GPT, there is no reason to use BSD disklabels at all.
disk ada0
GPT partition 1 (ada0p1, bootcode)
GPT partition 2 (ada0p2, /)
GPT partition 3 (ada0p3, swap)
GPT partition 4 (ada0p4, /var)
GPT partition 5 (ada0p5, /tmp)
GPT partition 6 (ada0p6, /usr)
Summary: "Dangerously dedicated" partitioning has no unique advantages.
Use GPT when possible, use MBR/disklabel when necessary.
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Re: dangerously dedicated physical disks.
On Sun, 22 Sep 2013, atar wrote:
During the reading of the FreeBSD handbook, I've encountered at the term
'dangerously dedicated' regarding physical disks and the author of this
chapter in the FreeBSD handbook didn't think this term need more clarity. so
for newbies like me in the FreeBSD world I want to ask: what's the
'dangerously dedicated' term meaning by?
The term refers to a disk partitioned with only the BSD disklabel
partition table:
disk ada0
partition "a" (ada0a, /)
partition "b" (ada0b, swap)
partition "d" (ada0d, /var)
partition "e" (ada0e, /tmp)
partition "f" (ada0f, /usr)
It's "dangerous" because that partitioning format is rare outside of
BSD-based systems. Disk utilities may not recognize it, and could
damage it.
Most of the rest of the world used MBR partitioning, which allowed up to
four MBR partitions (called "slices" by FreeBSD) per disk.
Since four slices is not enough for the standard FreeBSD disk layout,
with /, swap, /var, /tmp, and /usr, the standard procedure is to use MBR
partitioning, with the MBR partitions ("slices") being sub-partitioned
by a BSD disklabel.
disk ada0
MBR slice 1 (ada0s1)
partition "a" (ada0s1a, /)
partition "b" (ada0s1b, swap)
partition "d" (ada0s1d, /var)
partition "e" (ada0s1e, /tmp)
partition "f" (ada0s1f, /usr)
MBR slice 2 (ada0s2)
...
Yes, one partition format inside another. It only seems complicated
because it is.
GPT is the new partitioning format, which makes things much simpler by
being capable of up to 128 partitions in the standard configuration.
With GPT, there is no reason to use BSD disklabels at all.
disk ada0
GPT partition 1 (ada0p1, bootcode)
GPT partition 2 (ada0p2, /)
GPT partition 3 (ada0p3, swap)
GPT partition 4 (ada0p4, /var)
GPT partition 5 (ada0p5, /tmp)
GPT partition 6 (ada0p6, /usr)
Summary: "Dangerously dedicated" partitioning has no unique advantages.
Use GPT when possible, use MBR/disklabel when necessary.
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Re: dangerously dedicated physical disks.
Thanks. it helps a little to clarify this term. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated physical disks.
On Sun, 22 Sep 2013 16:16:17 - atar wrote: > Hi there!! > > During the reading of the FreeBSD handbook, I've encountered at the term > 'dangerously dedicated' regarding physical disks and the author of this > chapter in the FreeBSD handbook didn't think this term need more clarity. > so for newbies like me in the FreeBSD world I want to ask: what's the > 'dangerously dedicated' term meaning by? > > Thanks in advance! > > atar. > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" Information is at this (very old) link. Not as scary as it sounds. http://docs.freebsd.org/doc/2.2.6-RELEASE/usr/share/doc/FAQ/FAQ103.html ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
dangerously dedicated physical disks.
Hi there!! During the reading of the FreeBSD handbook, I've encountered at the term 'dangerously dedicated' regarding physical disks and the author of this chapter in the FreeBSD handbook didn't think this term need more clarity. so for newbies like me in the FreeBSD world I want to ask: what's the 'dangerously dedicated' term meaning by? Thanks in advance! atar. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated disks and 8-stable status
On Fri, May 07, 2010 at 10:06:31PM +0100, krad wrote: > On 7 May 2010 16:17, A. Wright wrote: > > > > > On Fri, 7 May 2010, krad wrote: > > > > FYI happened on 2nd box as well but I least it didnt catch me out this > >> time > >> 8). It seems that pre freebsd-8 it is permissible to use format > >> s1[a-h] , however in freebsd-8+ to you are forced to use the format > >> [a-h]. > >> > > > > I have noted peculiarities also in this move (as noted above: > > 8.0-RELEASE upgrade -- no files visible), but different ones > > from what you are seeing. > > > > I have begun to suspect that part of the issue is that my > > drives at one time were set up in "dangerously dedicated" > > mode, but later changed to "slice-based" mode. It may be > > that there are still sectors near the beginning of the disk > > with old information in them. > > > > Currently I have one disk remaining from the old setup, for > > which I only get /dev entries produced for the device, and > > for partition 'a' (ie, /dev/ad10, /dev/ad10a), however if > > accessed from 7.2, I can see and mount /dev/ad10s1[a,d-g]. > > > > Might your disks have similar "old" information in the first > > track (but not in the first sector), or do you refer to a > > new disk, or one to which a number of sectors of zeros was > > written? > > > > Thanks for the info, > > A. > > > > > > Both were a 6.2 box upgraded to 7-stable then 8. I didnt build the initial > os's so have no idea what the state of the disks were unfortunately. I have > about 20 more or so upgrades to do in the next few weeks so expect the trend > to continue as they were all built around the same time by the same person If you are worried that there might be something in an early sector on the disk, you can get rid of it by using dd(1). If your drive is /dev/ad10, then do the following. dd if=/dev/zero of=/dev/ad10 bs=512 count=1024 Actually any count over 32 should work, but it takes no time so use a biger one. This will work before slicing and partitioning the drive or will wipe out previous slicing and partitioning. jerry > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated disks and 8-stable status
On 7 May 2010 16:17, A. Wright wrote: > > On Fri, 7 May 2010, krad wrote: > > FYI happened on 2nd box as well but I least it didnt catch me out this >> time >> 8). It seems that pre freebsd-8 it is permissible to use format >> s1[a-h] , however in freebsd-8+ to you are forced to use the format >> [a-h]. >> > > I have noted peculiarities also in this move (as noted above: > 8.0-RELEASE upgrade -- no files visible), but different ones > from what you are seeing. > > I have begun to suspect that part of the issue is that my > drives at one time were set up in "dangerously dedicated" > mode, but later changed to "slice-based" mode. It may be > that there are still sectors near the beginning of the disk > with old information in them. > > Currently I have one disk remaining from the old setup, for > which I only get /dev entries produced for the device, and > for partition 'a' (ie, /dev/ad10, /dev/ad10a), however if > accessed from 7.2, I can see and mount /dev/ad10s1[a,d-g]. > > Might your disks have similar "old" information in the first > track (but not in the first sector), or do you refer to a > new disk, or one to which a number of sectors of zeros was > written? > > Thanks for the info, > A. > > > Both were a 6.2 box upgraded to 7-stable then 8. I didnt build the initial os's so have no idea what the state of the disks were unfortunately. I have about 20 more or so upgrades to do in the next few weeks so expect the trend to continue as they were all built around the same time by the same person ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated disks and 8-stable status
On Fri, 7 May 2010, krad wrote: FYI happened on 2nd box as well but I least it didnt catch me out this time 8). It seems that pre freebsd-8 it is permissible to use format s1[a-h] , however in freebsd-8+ to you are forced to use the format [a-h]. I have noted peculiarities also in this move (as noted above: 8.0-RELEASE upgrade -- no files visible), but different ones from what you are seeing. I have begun to suspect that part of the issue is that my drives at one time were set up in "dangerously dedicated" mode, but later changed to "slice-based" mode. It may be that there are still sectors near the beginning of the disk with old information in them. Currently I have one disk remaining from the old setup, for which I only get /dev entries produced for the device, and for partition 'a' (ie, /dev/ad10, /dev/ad10a), however if accessed from 7.2, I can see and mount /dev/ad10s1[a,d-g]. Might your disks have similar "old" information in the first track (but not in the first sector), or do you refer to a new disk, or one to which a number of sectors of zeros was written? Thanks for the info, A. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated disks and 8-stable status
On 5 May 2010 18:55, Polytropon wrote: > On Wed, 5 May 2010 17:17:09 +0100, krad wrote: > > I updated a production box at work last night from freebsd 6.2 to > 8-stable, > > via 7-stable. The upgrade went ok just a minor glitch in jumping from 7 > to > > 8. Basically all the device names changed from mfid0s1[a-g] to > mfid0[a-g]. I > > presume this is because the initial layout was in dangerously dedicated > > mode. > > That's strange. "Dangerously" dedicated partitioning omits the > slicing part, so if you had mfid0s1[a-g] in 6 and 7, there was > a slice. Maybe the mfi driver is different in 8 in terms of > representing the disks? > > > > > Two issues here why did the naming scheme seem to indicate a more > > normal MBR disk layout in bsd 6 and 7. > > Very strange - if you can check booting from a live system CD > or DVD with FreeBSD 6 and 7, and the disks are mfid0s1[a-g], > and if you boot into FreeBSD 8, the disks are mfid0[a-g], that's > really strange... > > > > > Second what is the current status of > > dangerously dedicated in 8-stable as i thought support was being dropped. > > The support has been removed from sysinstall. You can't create > dedicated partitions (without slice) with sysinstall, but you > can create them manually (e. g. using bsdlabel and newfs). So > support isn't dropped at all - dedicated disks just is a new > special secret feature. :-) > > > > -- > Polytropon > Magdeburg, Germany > Happy FreeBSD user since 4.0 > Andra moi ennepe, Mousa, ... > FYI happened on 2nd box as well but I least it didnt catch me out this time 8). It seems that pre freebsd-8 it is permissible to use format s1[a-h] , however in freebsd-8+ to you are forced to use the format [a-h]. # ls -ltr backup-2010-05-0[57]*/dev/mfid* crw-r- 1 root uucp 0, 90 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0s1g crw-r- 1 root uucp 0, 89 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0s1f crw-r- 1 root uucp 0, 88 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0s1e crw-r- 1 root uucp 0, 87 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0s1d crw-r- 1 root uucp 0, 84 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0s1a crw-r- 1 root uucp 0, 86 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0s1c crw-r- 1 root uucp 0, 85 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0s1b crw-r- 1 root uucp 0, 76 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0s1 crw-r- 1 root uucp 0, 75 Jan 12 2008 backup-2010-05-05_01:59--2010-05-05_02:29/dev/mfid0 crw-r- 1 root uucp 0, 87 May 7 04:38 backup-2010-05-07_13:57--2010-05-07_14:10/dev/mfid0b crw-r- 1 root uucp 0, 85 May 7 04:38 backup-2010-05-07_13:57--2010-05-07_14:10/dev/mfid0 crw-r- 1 root uucp 0, 91 May 7 05:38 backup-2010-05-07_13:57--2010-05-07_14:10/dev/mfid0g crw-r- 1 root uucp 0, 90 May 7 05:38 backup-2010-05-07_13:57--2010-05-07_14:10/dev/mfid0f crw-r- 1 root uucp 0, 89 May 7 05:38 backup-2010-05-07_13:57--2010-05-07_14:10/dev/mfid0e crw-r- 1 root uucp 0, 88 May 7 05:38 backup-2010-05-07_13:57--2010-05-07_14:10/dev/mfid0d crw-r- 1 root uucp 0, 86 May 7 05:38 backup-2010-05-07_13:57--2010-05-07_14:10/dev/mfid0a ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated disks and 8-stable status
On 5 May 2010 21:28, krad wrote: > > > On 5 May 2010 18:55, Polytropon wrote: > >> On Wed, 5 May 2010 17:17:09 +0100, krad wrote: >> > I updated a production box at work last night from freebsd 6.2 to >> 8-stable, >> > via 7-stable. The upgrade went ok just a minor glitch in jumping from 7 >> to >> > 8. Basically all the device names changed from mfid0s1[a-g] to >> mfid0[a-g]. I >> > presume this is because the initial layout was in dangerously dedicated >> > mode. >> >> That's strange. "Dangerously" dedicated partitioning omits the >> slicing part, so if you had mfid0s1[a-g] in 6 and 7, there was >> a slice. Maybe the mfi driver is different in 8 in terms of >> representing the disks? >> >> >> >> > Two issues here why did the naming scheme seem to indicate a more >> > normal MBR disk layout in bsd 6 and 7. >> >> Very strange - if you can check booting from a live system CD >> or DVD with FreeBSD 6 and 7, and the disks are mfid0s1[a-g], >> and if you boot into FreeBSD 8, the disks are mfid0[a-g], that's >> really strange... >> >> I agree, but it definitely happened, as i did the upgrade remotely. > Luckily the data center was only a mile or so away from my home, so it > wasn't a major disaster to console it, point the kernel at the correct > device and tweak fstab. COst me an hour more sleep than it had to though 8( > > I have another box to do in the next day or so. Is there anything you > recommend me looking at/running? Hopefully this box will have a drac card in > it 8) > >> >> >> > Second what is the current status of >> > dangerously dedicated in 8-stable as i thought support was being >> dropped. >> >> The support has been removed from sysinstall. You can't create >> dedicated partitions (without slice) with sysinstall, but you >> can create them manually (e. g. using bsdlabel and newfs). So >> support isn't dropped at all - dedicated disks just is a new >> special secret feature. :-) >> >> >> This was the bit i was worried about, as i didnt want to get caught out in > the future when I want to upgrade again > >> >> -- >> >> Polytropon >> Magdeburg, Germany >> Happy FreeBSD user since 4.0 >> Andra moi ennepe, Mousa, ... >> > > Hmm, things get a little strange on a box I built from scratch # bsdlabel /dev/mfid0 bsdlabel: /dev/mfid0: no valid label found # bsdlabel /dev/mfid0s1 # /dev/mfid0s1: 8 partitions: #size offsetfstype [fsize bsize bps/cpg] a: 419430404.2BSD 2048 16384 28528 b: 8388608 4194304 swap c: 2854589220unused0 0 # "raw" part, don't edit d: 16777216 125829124.2BSD 2048 16384 28528 e: 8388608 293601284.2BSD 2048 16384 28528 f: 8388608 377487364.2BSD 2048 16384 28528 g: 129954672 461373444.2BSD 2048 16384 28528 h: 109366906 1760920164.2BSD 2048 16384 28528 All fairly normal One the next box I have to upgrade (built by a former employee who was well known for his qwirky ways) # bsdlabel /dev/mfid0s1 # /dev/mfid0s1: 8 partitions: #size offsetfstype [fsize bsize bps/cpg] a: 209715204.2BSD 2048 16384 28528 b: 16777216 2097152 swap c: 1420820480unused0 0 # "raw" part, don't edit d: 16777216 188743684.2BSD 2048 16384 28528 e: 16777216 356515844.2BSD 2048 16384 28528 f: 16777216 524288004.2BSD 2048 16384 28528 g: 72876032 692060164.2BSD 2048 16384 28528 # bsdlabel /dev/mfid0 # /dev/mfid0: 8 partitions: #size offsetfstype [fsize bsize bps/cpg] a: 209715204.2BSD 2048 16384 28528 b: 16777216 2097152 swap c: 1420820480unused0 0 # "raw" part, don't edit d: 16777216 188743684.2BSD 2048 16384 28528 e: 16777216 356515844.2BSD 2048 16384 28528 f: 16777216 524288004.2BSD 2048 16384 28528 g: 72876032 692060164.2BSD 2048 16384 28528 not sure what he has done fdisk output is fairly normal on this box as well *** Working on device /dev/mfid0 *** parameters extracted from in-core disklabel are: cylinders=8844 heads=255 sectors/track=63 (16065 blks/cyl) Figures below won't work with BIOS for partitions not in cyl 1 parameters to be used for BIOS calculations are: cylinders=8844 heads=255 sectors/track=63 (16065 blks/cyl) Media sector size is 512 Warning: BIOS sector numbering starts with sector 1 Information from DOS bootblock is: The data for partition 1 is: sysid 165 (
Re: dangerously dedicated disks and 8-stable status
On 5 May 2010 18:55, Polytropon wrote: > On Wed, 5 May 2010 17:17:09 +0100, krad wrote: > > I updated a production box at work last night from freebsd 6.2 to > 8-stable, > > via 7-stable. The upgrade went ok just a minor glitch in jumping from 7 > to > > 8. Basically all the device names changed from mfid0s1[a-g] to > mfid0[a-g]. I > > presume this is because the initial layout was in dangerously dedicated > > mode. > > That's strange. "Dangerously" dedicated partitioning omits the > slicing part, so if you had mfid0s1[a-g] in 6 and 7, there was > a slice. Maybe the mfi driver is different in 8 in terms of > representing the disks? > > > > > Two issues here why did the naming scheme seem to indicate a more > > normal MBR disk layout in bsd 6 and 7. > > Very strange - if you can check booting from a live system CD > or DVD with FreeBSD 6 and 7, and the disks are mfid0s1[a-g], > and if you boot into FreeBSD 8, the disks are mfid0[a-g], that's > really strange... > > I agree, but it definitely happened, as i did the upgrade remotely. Luckily the data center was only a mile or so away from my home, so it wasn't a major disaster to console it, point the kernel at the correct device and tweak fstab. COst me an hour more sleep than it had to though 8( I have another box to do in the next day or so. Is there anything you recommend me looking at/running? Hopefully this box will have a drac card in it 8) > > > > Second what is the current status of > > dangerously dedicated in 8-stable as i thought support was being dropped. > > The support has been removed from sysinstall. You can't create > dedicated partitions (without slice) with sysinstall, but you > can create them manually (e. g. using bsdlabel and newfs). So > support isn't dropped at all - dedicated disks just is a new > special secret feature. :-) > > > This was the bit i was worried about, as i didnt want to get caught out in the future when I want to upgrade again > > -- > Polytropon > Magdeburg, Germany > Happy FreeBSD user since 4.0 > Andra moi ennepe, Mousa, ... > ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: dangerously dedicated disks and 8-stable status
On Wed, 5 May 2010 17:17:09 +0100, krad wrote: > I updated a production box at work last night from freebsd 6.2 to 8-stable, > via 7-stable. The upgrade went ok just a minor glitch in jumping from 7 to > 8. Basically all the device names changed from mfid0s1[a-g] to mfid0[a-g]. I > presume this is because the initial layout was in dangerously dedicated > mode. That's strange. "Dangerously" dedicated partitioning omits the slicing part, so if you had mfid0s1[a-g] in 6 and 7, there was a slice. Maybe the mfi driver is different in 8 in terms of representing the disks? > Two issues here why did the naming scheme seem to indicate a more > normal MBR disk layout in bsd 6 and 7. Very strange - if you can check booting from a live system CD or DVD with FreeBSD 6 and 7, and the disks are mfid0s1[a-g], and if you boot into FreeBSD 8, the disks are mfid0[a-g], that's really strange... > Second what is the current status of > dangerously dedicated in 8-stable as i thought support was being dropped. The support has been removed from sysinstall. You can't create dedicated partitions (without slice) with sysinstall, but you can create them manually (e. g. using bsdlabel and newfs). So support isn't dropped at all - dedicated disks just is a new special secret feature. :-) -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
dangerously dedicated disks and 8-stable status
I updated a production box at work last night from freebsd 6.2 to 8-stable, via 7-stable. The upgrade went ok just a minor glitch in jumping from 7 to 8. Basically all the device names changed from mfid0s1[a-g] to mfid0[a-g]. I presume this is because the initial layout was in dangerously dedicated mode. Two issues here why did the naming scheme seem to indicate a more normal MBR disk layout in bsd 6 and 7. Second what is the current status of dangerously dedicated in 8-stable as i thought support was being dropped. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: Dangerously Dedicated
On Thu, Dec 10, 2009 at 10:43:37AM -0500, Robert Huff wrote:
>
> Jerry McAllister writes:
>
> > It is dedicated because only FreeBSD can talk to it.
>
> Is this correct? What about {Net, Open, DregonFly}BSD, or
> Linux?
>
Not Linux without some programming, but maybe some of the other BSDs.
jerry
>
> Robert Huff
>
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Re: Dangerously Dedicated
Jerry McAllister writes:
> It is dedicated because only FreeBSD can talk to it.
Is this correct? What about {Net, Open, DregonFly}BSD, or
Linux?
Robert Huff
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Re: Dangerously Dedicated
On Thu, Dec 10, 2009 at 03:08:16AM +0100, Polytropon wrote: > On Thu, 10 Dec 2009 02:33:17 +0100, Rolf Nielsen > wrote: > > As far as I understand it, it's called Dangerously Dedicated because it > > may cause other systems not to recognise the disk. > > Primarily, it's called "dedicated" (only) because it describes > a setting where a whole hard disk is dedicated to the FreeBSD > operating system. The addition "dangerously" seems to describe > the danger that other operating systems cannot handle such a > disk layout, or may cause problems to them - but I don't know > this for sure because I'm not a "multi-booter". :-) It is dangerous because other systems cannot talk to it. It is dedicated because only FreeBSD can talk to it. It is a somewhat redundant term but it sounds good and important. jerry ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: Dangerously Dedicated
On Thu, 10 Dec 2009 00:04:28 -0800 (PST), James Phillips wrote: > The Detailed 8.0 release notes don't say anything about bootability: > 2.2.5 File Systems > “dangerously dedicated” mode for the UFS file system > is no longer supported > http://www.freebsd.org/releases/8.0R/relnotes-detailed.html Okay, but what happens when you # newfs /dev/ad1 in the assumption that ad1 will be a pure data disk, and issuing this command will create a partition covering the whole ad1 disk without any slice, and then create an UFS file system in this partition? I cannot imagine that this shouldn't be possible anymore. I'm convinced that abandoning DD for bootable disks is completely understandable, but... Where are the points when problem occur? (I've got no 8.0 installation at hand so I can't check this in a live setting.) > I also note that the DOS partition (slice) table is not explictly > required either: could you use an Apple partiton (slice) table > instead? I don't know how they differ from each other. > Of course, if you are just storing raw data, you don't always *need* > a filesystem. You can of course simply use tar (as the "most universal file system, at least among UNIXes") on a raw disk, e. g. tar cf /lots/of/files /dev/ad1 and retrieve it using tar xf /dev/ad1 But in the common case of a pure data disk, as I mentioned it above, you have a file system (inside a partition), but no slice. In such a case, the fdisk utility will show a sysid 165 partition for the disk, just as if a slice would be present. I'm interested in knowing where this will end. FreeBSD defaulting to FAT file system for maximum compatibility? Don't mind, just a joke. It will of course use NTFS. :-) -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: Dangerously Dedicated
> Date: Thu, 10 Dec 2009 03:12:45 +0100
> From: Polytropon
> Subject: Re: Dangerously Dedicated
> To: Maxim Khitrov
> Cc: freebsd-questions@freebsd.org
> Message-ID: <20091210031245.3fd58187.free...@edvax.de>
> Content-Type: text/plain; charset=US-ASCII
>
> On Wed, 9 Dec 2009 20:41:40 -0500, Maxim Khitrov
> wrote:
> > On Wed, Dec 9, 2009 at 8:33 PM, Rolf Nielsen
> >
> wrote:
> > > As far as I understand it, it's called
> Dangerously Dedicated because it may
> > > cause other systems not to recognise the disk.
> Consequently, newfs'ing a
> > > slice without first partitioning it can hardly be
> DD, since that is what
> > > other systems do, right?
I think I understand: using the DOS compatible partition (slice)
table follows the principle of "least surprise." That is why I use
"slices" for my dedicated BSD machine. 4 places to put your data are
ostensibly better than 1, and I avoid any possible BIOS bugs if the
BIOS sees a "non-standard" MBR.
> >
> > That is correct. That slice will not be bootable, but
> you can use it
> > to store data.
>
> Being bootable is a matter of what the MBR boot block
> says. In a DD setting, it refers to the first partition
> (that's not within a slice), e. g. ad0a. Especially in
> a multi-OS setting, the use of slices seems to be
> strongly recommended so all operating systems behave
> in the required way (due to compatibility reasons,
> see "DOS primary partitions"), which limits the number
> of slices to 4.
I would say a common partition format is REQUIRED in a multi-boot
situation. For PC OS's, that means DOS compatibility.
> For plain storage, it's not needed to encapsulate the
> partition with the file system inside a slice, e. g.
>
> ad1 ad1s1 ad1s1e
> { [
> (/data) ] }
>
> in comparison to
>
> ad1 ad1c
> { (/data) }
>
> And as it is known, the "c" can be omitted, as in
>
> # mount /dev/ad1 /data
>
>
The Detailed 8.0 release notes don't say anything about bootability:
2.2.5 File Systems
“dangerously dedicated” mode for the UFS file system
is no longer supported
http://www.freebsd.org/releases/8.0R/relnotes-detailed.html
I also note that the DOS partition (slice) table is not explictly
required either: could you use an Apple partiton (slice) table
instead?
UFS not supporting DD mode struck me as weird BECAUSE it has to work
with different architectures.
Of course, if you are just storing raw data, you don't always *need*
a filesystem.
Regards,
James Phillips
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Re: Dangerously Dedicated
On Wed, 9 Dec 2009 20:41:40 -0500, Maxim Khitrov wrote:
> On Wed, Dec 9, 2009 at 8:33 PM, Rolf Nielsen
> wrote:
> > As far as I understand it, it's called Dangerously Dedicated because it may
> > cause other systems not to recognise the disk. Consequently, newfs'ing a
> > slice without first partitioning it can hardly be DD, since that is what
> > other systems do, right?
>
> That is correct. That slice will not be bootable, but you can use it
> to store data.
Being bootable is a matter of what the MBR boot block
says. In a DD setting, it refers to the first partition
(that's not within a slice), e. g. ad0a. Especially in
a multi-OS setting, the use of slices seems to be
strongly recommended so all operating systems behave
in the required way (due to compatibility reasons,
see "DOS primary partitions"), which limits the number
of slices to 4.
For plain storage, it's not needed to encapsulate the
partition with the file system inside a slice, e. g.
ad1 ad1s1 ad1s1e
{[ (/data) ] }
in comparison to
ad1 ad1c
{(/data) }
And as it is known, the "c" can be omitted, as in
# mount /dev/ad1 /data
--
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...
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Re: Dangerously Dedicated
On Thu, 10 Dec 2009 02:33:17 +0100, Rolf Nielsen
wrote:
> As far as I understand it, it's called Dangerously Dedicated because it
> may cause other systems not to recognise the disk.
Primarily, it's called "dedicated" (only) because it describes
a setting where a whole hard disk is dedicated to the FreeBSD
operating system. The addition "dangerously" seems to describe
the danger that other operating systems cannot handle such a
disk layout, or may cause problems to them - but I don't know
this for sure because I'm not a "multi-booter". :-)
> Consequently,
> newfs'ing a slice without first partitioning it can hardly be DD, since
> that is what other systems do, right?
If you run newfs inside a slice, you would create a partition
covering the whole slice, and so it's still compatibility mode
(the opposite of DD mode); DD mode implies the absence of a
slice at all.
da0 da0s1 da0s1c
{[ (/) ] }
Other systems operate on slice level, on a "DOS primary partition",
where they create their file systems in a certain way, e. g.
an msdos file system. In such a case, there are no partitions
inside the slice because partitions are specific to operating
systems like FreeBSD.
da0 da0s1da0s2da0s3 da0s3a
{[ C: ] [ D: ] [ (/) ] }
msdosfs msdosfs ufs
--
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
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Re: Dangerously Dedicated
On Wed, Dec 9, 2009 at 8:33 PM, Rolf Nielsen wrote: > RW wrote: >> >> On Wed, 9 Dec 2009 11:42:31 -0800 (PST) >> James Phillips wrote: >> >> >>> I sort of followed the discussion as well. There was some disagreement >>> about what "dangreously dedicated" means. Does it mean getting rid of the >>> DOS partition table (slices?) Or, does it mean creating a slice or disks >>> without BSD partitions? >> >> It means the former. >> > > As far as I understand it, it's called Dangerously Dedicated because it may > cause other systems not to recognise the disk. Consequently, newfs'ing a > slice without first partitioning it can hardly be DD, since that is what > other systems do, right? That is correct. That slice will not be bootable, but you can use it to store data. - Max ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: Dangerously Dedicated
RW wrote: On Wed, 9 Dec 2009 11:42:31 -0800 (PST) James Phillips wrote: I sort of followed the discussion as well. There was some disagreement about what "dangreously dedicated" means. Does it mean getting rid of the DOS partition table (slices?) Or, does it mean creating a slice or disks without BSD partitions? It means the former. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" As far as I understand it, it's called Dangerously Dedicated because it may cause other systems not to recognise the disk. Consequently, newfs'ing a slice without first partitioning it can hardly be DD, since that is what other systems do, right? ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: Dangerously Dedicated (was: How do I create large ...)
On Wed, 9 Dec 2009 11:42:31 -0800 (PST) James Phillips wrote: > I sort of followed the discussion as well. There was some > disagreement about what "dangreously dedicated" means. Does it mean > getting rid of the DOS partition table (slices?) Or, does it mean > creating a slice or disks without BSD partitions? It means the former. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: Dangerously Dedicated (was: How do I create large ...)
On Wed, 9 Dec 2009 11:42:31 -0800 (PST), James Phillips
wrote:
> I sort of followed the discussion as well. There was some
> disagreement about what "dangreously dedicated" means.
For comparison, I seem to remember that the two concepts
are called "compatibility mode" and "(dangerously) dedicated
mode", with the "dangerously" looking like a further
addition.
> Does it mean
> getting rid of the DOS partition table (slices?)
The use of slices - "DOS primary partitions" has often been
suggested for FreeBSD, but it has always worked without them.
I think the neccessarity to use them is what I said before:
compatibility. FreeBSD can handle "no slices" well, but
maybe other operating systems and "Windows" can't?
A common problem is that due do compatibility (again),
the number of slices is limited to 4.
> Or, does it mean
> creating a slice or disks without BSD partitions?
How should this be possible? A partition (not a "DOS primary
partition", to avoid misunderstandings) is required for
creating a file system. Let's say you want to create a
file system on a disk:
# newfs da0
This means that a partition is created - da0c - and inside
this partition the file system resides.
This is a common method for accessing data disks (disks
you don't boot from).
> The Handbook (18.3)
> says: "If the disk is going to be truly dedicated to FreeBSD, you
> can use the dedicated mode. Otherwise, FreeBSD will have to live
> within one of the PC BIOS partitions. FreeBSD calls the PC BIOS
> partitions slices so as not to confuse them with traditional BSD
> partitions."
Exactly. No "dangerously" here.
> The programer in charge of the change seemed to indicate that the
> "Dangerously dedicated" mode (I assume that means no BSD partititons)
> conflicts with "GEOM: Modular Disk Transformation Framework."
No. It means "absence of a slice carrying the partitions",
which is the dedicated approach.
> GEOM
> appears to be an asbtraction layer for accessing various disks. With
> the move underway to start accessing all disk as SCSI(3 is device
> independent (with translation help)) devices, it probably makes for
> more elegant code. Handbook (19.2 GEOM Introduction) reads:
> "GEOM permits access and control to classes -- Master Boot Records,
> BSD labels, etc -- through the use of providers, or the special files
> in /dev. Supporting various software RAID configurations, GEOM will
> transparently provide access to the operating system and operating
> system utilities."
> The important thing in that quote is that "BSD labels" (and Master
> Boot Records) are mentioned specificly.
That's correct. BSD labels, usually created by disklabel,
refer to FreeBSD partitions. MBR refers to slices (this
is "DOS primary partitions", and maybe includes "logical
volumes inside a DOS extended partition", all the things
that produce "drive letters").
The only thing I can conclude from this is that the removal
of dedicated mode is due to increasing compatibility with
the abilities of GEOM...
I've got lots of ? flying around my head... :-)
Allow me to try a summary:
Dedicated mode (also "dangerously dedicated mode"):
da0 da0a da0b da0d da0e da0f da0g
{(/)(swap) (/tmp) (/var) (/usr) (/home) }
Compatibility mode:
da0 da0s1 da0s1a da0s1b da0s1d da0s1e da0s1f da0s1g
{[ (/)(swap) (/tmp) (/var) (/usr) (/home) ] }
I'm not sure hgow this fits into the concept of installing
multiple operating systems. For example, "Windows" requires
you to install it in a slice. No problem with compatibility
mode, but does this work in dedicated mode, too? I think the
suggestion is "No, does not work" simply because the disk is
DEDICATED to FreeBSD.
--
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...
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Re: Dangerously Dedicated (was: How do I create large ...)
> Date: Tue, 8 Dec 2009 22:00:29 +0100 > From: Polytropon > Subject: Re: How do I create large partitions in FreeBSD? > To: krad > Cc: Peter Steele , > "freebsd-questions@freebsd.org" > > Message-ID: <20091208220029.2052102f.free...@edvax.de> > Content-Type: text/plain; charset=US-ASCII > > On Tue, 8 Dec 2009 20:52:52 +0000, krad > wrote: > > stay away from dangerously dedicated it seems as > though they are being > > phased out > > I've followed the related discussion, but I'm not sure > what > to conclude from it... as far as I understood, creating an > installation "dangerously dedicated" mode isn't possible > from sysinstall anymore, but still possible via the > command > line tools. I don't see a reason why it is considered to > be > something bad, but the inclusion of a "carrier slice" for > the OS's partitions has always been recommended. But for > data disks where only one partition is intended, why > create > it inside a slice? > I sort of followed the discussion as well. There was some disagreement about what "dangreously dedicated" means. Does it mean getting rid of the DOS partition table (slices?) Or, does it mean creating a slice or disks without BSD partitions? The Handbook (18.3) says: "If the disk is going to be truly dedicated to FreeBSD, you can use the dedicated mode. Otherwise, FreeBSD will have to live within one of the PC BIOS partitions. FreeBSD calls the PC BIOS partitions slices so as not to confuse them with traditional BSD partitions." The programer in charge of the change seemed to indicate that the "Dangerously dedicated" mode (I assume that means no BSD partititons) conflicts with "GEOM: Modular Disk Transformation Framework." GEOM appears to be an asbtraction layer for accessing various disks. With the move underway to start accessing all disk as SCSI(3 is device independent (with translation help)) devices, it probably makes for more elegant code. Handbook (19.2 GEOM Introduction) reads: "GEOM permits access and control to classes -- Master Boot Records, BSD labels, etc -- through the use of providers, or the special files in /dev. Supporting various software RAID configurations, GEOM will transparently provide access to the operating system and operating system utilities." The important thing in that quote is that "BSD labels" (and Master Boot Records) are mentioned specificly. Regards, James Phillips __ Yahoo! Canada Toolbar: Search from anywhere on the web, and bookmark your favourite sites. Download it now http://ca.toolbar.yahoo.com. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
Polytropon wrote: On Wed, 2 Dec 2009 13:09:22 -0500, Jerry McAllister wrote: Good. Except that in FreeBSD land you are talking about a slice table. To carry things forward consistently, the partition table is within a slice and describes FreeBSD partitions a..h (and more now I guess). Only in MS or Lunix land should primary divisions be called partitions and then they are _primary_ partitions. To be most precise, they are called "DOS primary partitions". As far as I know, the need for them has been massively by MICROS~1 operating systems (DOS, "Windows"). That what FreeBSD calls partitions are subdivions of slices. A partition holds a file system (each), while a slice holds partitions. Those partitions could be compared to what MICROS~1 calls "logical volumes inside a DOS extended partition", allthoug that's just a *comparison* and not an exact equivalent. But, even some of the fdisk and other documentation still mucks this up and occasionally refers to slices as partitions. Maybe we can come up with some new terminology like 'blobs' and 'dollops' to get away from the problem. Borrow some artificially created fantasy words from modern KDE or Gnome application development? :-) An idea that follows your inspiration could be: (old) slice => (new) primary partition eq. DOS primary partition (old) partition => (new) secondary partition, alt. (new) subpartition comp. logical volumes inside a DOS extended partition But it would help to get at least FreeBSD's documentation consistent, even if it uses the non-MICROS~1 names for things (which is very fine for me). Note that the limitation to 4 slices per disk - we remember that we are talking about "DOS primary partitions" here - is grounded in the fact that MICROS~1 stuff doesn't seem to be able to handle more than 4, a legacy restriction from the past. I've not yet tested if it's possible to create e. g. ad0s1, ad0s2, ad0s3, ad0s4 and ad0s5 with FreeBSD, but it should be possible. (Because multi-booting PCs respectively their operating systems eat up primary partitions like coockies, often people complain that they can't install FreeBSD because it requires a primary partition as well. Mostly, people don't have 4 OSes on their disks, but the one or two they often have (e. g. a Linux and a "Windows") have already occupied adX0..adX3.) Hi all, Out of curiousity, I just tested to bsdlabel a disk I had lying around. In dangerously dedicated mode. No problem at all. I newfs'd it and mounted it. Also no problem. I haven't tried to boot from it though, but I may do that later, when I have nothing running that can't be halted. I did config -x /boot/kernel/kernel and I noticed that GEOM_PART_BSD was there, though I'm absolutely certain I haven't included it, and if I understand correctly, it shouldn't be there unless explicitly included? I'm running 8.0-RELEASE-p1 amd64 with a custom kernel config. However the kernel config file was more or less copied from 7.2, with just a little tweaking. I guess I should create a new one, using sys/conf/NOTES and sys/amd64/conf/NOTES as guidelines and sys/amd64/conf/GENERIC as template, but I haven't gotten around to that yet. Anyway, is GEOM_PART_BSD supposed to be there (I just checked, and noticed it's in sys/amd64/conf/DEFAULTS) or can I safely remove it? And will it, considering I migrated to gpt and zfs, be meaningful to remove it (e.g. will it make the kernel smaller or have any positive impact on zfs performance)? And should DD disks work except to boot from, or shouldn't they work at all? Sincerely, Rolf Nielsen ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Tue, Dec 01, 2009 at 08:34:05PM -0800, Randi Harper wrote: > I'm going to just reply to all of these at once. > > On Tue, Dec 1, 2009 at 1:03 PM, Jerry McAllister wrote: > > On Tue, Dec 01, 2009 at 07:59:42AM -0500, Maxim Khitrov wrote: > > > On Sat, Nov 28, 2009 at 12:28 PM, Peggy Wilkins wrote: > > > > Due to history I won't go into, all my production (currently > > > > 7.2-RELEASE) systems are installed onto "dangerously dedicated" > > > > disks. What exactly do I need to do to upgrade them to 8.0? > > > > (I'm not asking for an upgrade procedure, I'm familiar with > > > > that, but rather, how this change impacts the upgrade.) I think > > > > that the suggestion that the disks need to be reformatted is > > > > extreme and I hope something less extreme will suffice. > > Just to point out the obvious, you shouldn't use "dangerous" and > "production" in the same sentence. :) Fun with ambiguities aside, I think it's fair and reasonable to interpret "dedicated" as "dedicated to FreeBSD", and "dangerous" as "may not work with common third-party disk tools or an older BIOS". It's similarly fair to interpret any caveat, implicit or otherwise, against using "dangerously dedicated mode" as a general recommendation aimed at new users (typically in dual or multi-boot environments), and not a statement that dangerously dedicated mode is unsuitable for production environments. It certainly doesn't state or suggest that it's a convenient but deprecated feature that might be removed without notice or warning in the future. Which is what's happened. In that light, the statement in the release notes merits a fuller description as well as an explanation for the change. > > > > Also, just to be clear, does this statement refer to boot disks, > > > > data disks, or both? > > > > > > > > It doesn't make sense to me that "dangerously dedicated" could > > > > have an impact on UFS filesystems specifically. A partition > > > > table is just a partition table, regardless of what filesystems > > > > might be written on disks, yes? Am I misunderstanding something > > > > here? > > > > I don't know why it would have an affect, but they say it does. > > Did you see all the mailing list chatter about new installations > > failing due to sysinstall not being able to newfs device names that > > didn't exist? This is related. Also, a partition table isn't just a > > partition table. It's a little more complex than that. It has > > *nothing* to do with the filesystems inside. It has everything to do > > with the way that FreeBSD looks at the drive to figure out what's on > > it. See man pages for geom/gpart. There are others that have given a > > better explanation than I can provide (marcus, juli). Search the > > archives. FreeBSD is known for, among other things, the consistent quality of its documentation. As it stands, the statement "dangerously dedicated mode for the UFS file system is no longer supported" in the release notes stands in direct contradiction to the official Handbook (updated to include 8.0-RELEASE) Section 18.3.2.2 which states "you may use the dedicated mode". A suggestion to search the (multiple) archives for chatter suggests that authoritative information can now be found on display in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying "Beware of the Leopard". Perhaps you could provide something more specific, or a direct link to the chatter? > Trust me, I didn't remove DD support from sysinstall just to > > make life more complicated for everyone. I did this because as it > > stands right now, it doesn't work. Regrettably, the end result is the same. That's not to say we wouldn't grumble and then happily settle for something less. Provided that something amounted to more than "no longer supported because it doesn't work". -- George ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Wed, 2 Dec 2009 13:09:22 -0500, Jerry McAllister wrote: > Good. Except that in FreeBSD land you are talking about a slice table. > To carry things forward consistently, the partition table is within > a slice and describes FreeBSD partitions a..h (and more now I guess). > Only in MS or Lunix land should primary divisions be called partitions > and then they are _primary_ partitions. To be most precise, they are called "DOS primary partitions". As far as I know, the need for them has been massively by MICROS~1 operating systems (DOS, "Windows"). That what FreeBSD calls partitions are subdivions of slices. A partition holds a file system (each), while a slice holds partitions. Those partitions could be compared to what MICROS~1 calls "logical volumes inside a DOS extended partition", allthoug that's just a *comparison* and not an exact equivalent. > But, even some of the fdisk and other documentation still mucks this > up and occasionally refers to slices as partitions. Maybe we can > come up with some new terminology like 'blobs' and 'dollops' to get > away from the problem. Borrow some artificially created fantasy words from modern KDE or Gnome application development? :-) An idea that follows your inspiration could be: (old) slice => (new) primary partition eq. DOS primary partition (old) partition => (new) secondary partition, alt. (new) subpartition comp. logical volumes inside a DOS extended partition But it would help to get at least FreeBSD's documentation consistent, even if it uses the non-MICROS~1 names for things (which is very fine for me). Note that the limitation to 4 slices per disk - we remember that we are talking about "DOS primary partitions" here - is grounded in the fact that MICROS~1 stuff doesn't seem to be able to handle more than 4, a legacy restriction from the past. I've not yet tested if it's possible to create e. g. ad0s1, ad0s2, ad0s3, ad0s4 and ad0s5 with FreeBSD, but it should be possible. (Because multi-booting PCs respectively their operating systems eat up primary partitions like coockies, often people complain that they can't install FreeBSD because it requires a primary partition as well. Mostly, people don't have 4 OSes on their disks, but the one or two they often have (e. g. a Linux and a "Windows") have already occupied adX0..adX3.) -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Wed, Dec 02, 2009 at 10:30:10AM -0500, Bob Johnson wrote: > On 11/28/09, Peggy Wilkins wrote: > > Can someone elaborate on what exactly this statement in the 8.0 > > detailed release notes means? > > > > http://www.freebsd.org/releases/8.0R/relnotes-detailed.html#FS > > > >> 2.2.5 File Systems > >> > >> ?dangerously dedicated? mode for the UFS file system is no longer > >> supported. > >> > >> Important: Such disks will need to be reformatted to work with this > >> release. > > > [...snip...] > > > > It doesn't make sense to me that "dangerously dedicated" could have an > > impact on UFS filesystems specifically. A partition table is just a > > partition table, regardless of what filesystems might be written on > > disks, yes? Am I misunderstanding something here? > > > > Unless someone has changed the meaning of the term in the last few > years, a "dangerously dedicated" disk is one that has the FreeBSD file > system on it with no partition table. It is basically an artifact of > the pre-Microsoft origin of BSD (there were reasons it stayed around, > but they ought to be ancient history by now). Since UFS is the > standard FreeBSD filesystem, DD disks contain UFS filesystems almost > by definition. > > So, to get to the main point of your confusion (and unless I am the > one that is very confused), "dangerously dedicated" disks do not have > partition tables. That's what makes them dangerous. It confuses things > that expect to find a partition table. > > If your partition name has an "s" (slice number) in it (e.g. ad2s1a) > it is not "dangerously dedicated". A "DD" disk partition would have a > name like "ad2a" with no slice number. At least, that's the way it > used to be. I quit using DD disks years ago when it became clear to me > that the unintended side effects aren't worth the few bytes you save. > Every once in a while a BIOS, or a utility, or something else pops up > that expects to find a partition table and gets confused without it. > It appears that it has happened again. > > > Thanks for helping to clear up my confusion... > > I hope I helped. Good. Except that in FreeBSD land you are talking about a slice table. To carry things forward consistently, the partition table is within a slice and describes FreeBSD partitions a..h (and more now I guess). Only in MS or Lunix land should primary divisions be called partitions and then they are _primary_ partitions. But, even some of the fdisk and other documentation still mucks this up and occasionally refers to slices as partitions. Maybe we can come up with some new terminology like 'blobs' and 'dollops' to get away from the problem. jerry > > -- > -- Bob Johnson >fbsdli...@gmail.com > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" > ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Wed, Dec 02, 2009 at 09:48:05AM -0800, Randi Harper wrote: > On Wed, Dec 2, 2009 at 7:23 AM, Jerry McAllister wrote: > > Some of the responses have said that UFS handling of 'Dangerously > > dedicated' has not gone away, just sysinstall handling of it. > > That may be true and if that is true, then you can probably still > > access dangerously dedicated drives. But, I would think it is a > > good opportunity to convert them while the uncertainty reigns. > > Once again, it has nothing at all to do with UFS. Clearly you didn't > search the mailing list archives like I said you should. I removed the > support from sysinstall because it was *broken* due to changes with > geom. It is not a sysinstall thing, it's a "oh look, sysinstall lets > you do something that doesn't work anymore" thing. You'd think if the > person that made these changes to sysinstall was commenting on the > issue, that should clear up any uncertainty. But you can go ahead > believing whatever makes you happy. OK. If it is a geom thing, then its a geom thing. The statement that it might be a good time to convert dangerously dedicated disks to sliced and partitioned drives is still the point of the piece you quoted and still is valid. ALthough I have made a few DD disks in the past, I do not run with them and so don't really care other than someone was asking about it. Since I do not use DD disks, I am assuming this doesn't affect me. For someone else, the best thing to do is back up their stuff, rebuild the disk with the appropriate utilities (fdisk/bsdlabel/newfs or whatever works for you) and restore their stuff. jerry > > -- randi > ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Wed, Dec 2, 2009 at 7:23 AM, Jerry McAllister wrote: > Some of the responses have said that UFS handling of 'Dangerously > dedicated' has not gone away, just sysinstall handling of it. > That may be true and if that is true, then you can probably still > access dangerously dedicated drives. But, I would think it is a > good opportunity to convert them while the uncertainty reigns. Once again, it has nothing at all to do with UFS. Clearly you didn't search the mailing list archives like I said you should. I removed the support from sysinstall because it was *broken* due to changes with geom. It is not a sysinstall thing, it's a "oh look, sysinstall lets you do something that doesn't work anymore" thing. You'd think if the person that made these changes to sysinstall was commenting on the issue, that should clear up any uncertainty. But you can go ahead believing whatever makes you happy. -- randi ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Tue, Dec 01, 2009 at 08:34:05PM -0800, Randi Harper wrote: > I'm going to just reply to all of these at once. > > On Tue, Dec 1, 2009 at 1:03 PM, Jerry McAllister wrote: > > On Tue, Dec 01, 2009 at 07:59:42AM -0500, Maxim Khitrov wrote: > > > >> On Sat, Nov 28, 2009 at 12:28 PM, Peggy Wilkins wrote: > >> > Due to history I won't go into, all my production (currently > >> > 7.2-RELEASE) systems are installed onto "dangerously dedicated" disks. > >> > What exactly do I need to do to upgrade them to 8.0? (I'm not asking > >> > for an upgrade procedure, I'm familiar with that, but rather, how this > >> > change impacts the upgrade.) I think that the suggestion that the > >> > disks need to be reformatted is extreme and I hope something less > >> > extreme will suffice. > > > Just to point out the obvious, you shouldn't use "dangerous" and > "production" in the same sentence. :) It may be a less than optimal idea, but many disks used in production have been implemented using the dangerously dedicated method. > >> > Also, just to be clear, does this statement refer to boot disks, data > >> > disks, or both? > >> > > >> > It doesn't make sense to me that "dangerously dedicated" could have an > >> > impact on UFS filesystems specifically. A partition table is just a > >> > partition table, regardless of what filesystems might be written on > >> > disks, yes? Am I misunderstanding something here? > > > > I don't know why it would have an affect, but they say it does. > > Did you see all the mailing list chatter about new installations > failing due to sysinstall not being able to newfs device names that > didn't exist? This is related. Also, a partition table isn't just a > partition table. It's a little more complex than that. It has > *nothing* to do with the filesystems inside. It has everything to do > with the way that FreeBSD looks at the drive to figure out what's on > it. See man pages for geom/gpart. There are others that have given a > better explanation than I can provide (marcus, juli). Search the > archives. Trust me, I didn't remove DD support from sysinstall just to > make life more complicated for everyone. I did this because as it > stands right now, it doesn't work. > > > > I take this to mean that any disk that is created without slice > > and partition within slice needs to be redone. Probably it can all > > be done in sysinstall, but you can do it with fdisk/bsdlabel/newfs. > > > Or sade, although sade hasn't yet been updated to reflect the lack of > DD support. Just don't use that option. Yah, there are other disk building utilities. > > It does not matter if it is a boot disk or just a data disk. It > > is whether or not it has a (one or more, up to 4) slice defined > > and within the slice[s] partitions defined which are turned in to > > filesystems. You can tell by the dev names in /etc/fstab. > > > > If they have the full device name /dev/da0s1a, ... da0s1h, they > > are NOT dangerously dedicated and you should not have to worry. > > > > If the machine is dual booted with some MS thing as the other OS, then > > it is very unlikely that they are dangerously dedicated. > > > > But, if they are like /dev/da0 or /dev/da0s1 (but with no 'a, b..h') > > then they are dangerously dedicated and you need to convert them. > > > What? No. 's1' refers to slice 1 (or partition 1, as you're referring > to it). bsdlabel is used inside this slice to create a partition for > each mount point (a,b,c, etc). See > http://www.freebsd.org/doc/en/articles/formatting-media/x76.html. This > documentation needs to be updated, but at least it'll give you a good > explanation of how it used to work. With DD mode, you're creating a > label against the drive itself, not a slice within. Yes, I am probably conflating a couple of similar things. But, I have seen 'dangerously dedicated' used to describe both situations and so included both here. > > > First you would have to back up the contents of the disk, partition > > by partition (mountable filesystem by mountable filesystem) however > > you have it. Since it is 'dangerously dedicated' it is likely you > > have a single filesystem per disk that needs backing up. > > Check out that backup to make sure it is readable. There is no > > going back. The backup can be done to tape or USB external disk > > or net
Re: 8.0-RELEASE and "dangerously dedicated" disks
On 11/28/09, Peggy Wilkins wrote: > Can someone elaborate on what exactly this statement in the 8.0 > detailed release notes means? > > http://www.freebsd.org/releases/8.0R/relnotes-detailed.html#FS > >> 2.2.5 File Systems >> >> “dangerously dedicated” mode for the UFS file system is no longer >> supported. >> >> Important: Such disks will need to be reformatted to work with this >> release. > [...snip...] > > It doesn't make sense to me that "dangerously dedicated" could have an > impact on UFS filesystems specifically. A partition table is just a > partition table, regardless of what filesystems might be written on > disks, yes? Am I misunderstanding something here? > Unless someone has changed the meaning of the term in the last few years, a "dangerously dedicated" disk is one that has the FreeBSD file system on it with no partition table. It is basically an artifact of the pre-Microsoft origin of BSD (there were reasons it stayed around, but they ought to be ancient history by now). Since UFS is the standard FreeBSD filesystem, DD disks contain UFS filesystems almost by definition. So, to get to the main point of your confusion (and unless I am the one that is very confused), "dangerously dedicated" disks do not have partition tables. That's what makes them dangerous. It confuses things that expect to find a partition table. If your partition name has an "s" (slice number) in it (e.g. ad2s1a) it is not "dangerously dedicated". A "DD" disk partition would have a name like "ad2a" with no slice number. At least, that's the way it used to be. I quit using DD disks years ago when it became clear to me that the unintended side effects aren't worth the few bytes you save. Every once in a while a BIOS, or a utility, or something else pops up that expects to find a partition table and gets confused without it. It appears that it has happened again. > Thanks for helping to clear up my confusion... I hope I helped. -- -- Bob Johnson fbsdli...@gmail.com ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Tue, Dec 1, 2009 at 11:34 PM, Randi Harper wrote: > I'm going to just reply to all of these at once. > > On Tue, Dec 1, 2009 at 1:03 PM, Jerry McAllister wrote: >> On Tue, Dec 01, 2009 at 07:59:42AM -0500, Maxim Khitrov wrote: >> >>> On Sat, Nov 28, 2009 at 12:28 PM, Peggy Wilkins wrote: >>> > Due to history I won't go into, all my production (currently >>> > 7.2-RELEASE) systems are installed onto "dangerously dedicated" disks. >>> > What exactly do I need to do to upgrade them to 8.0? (I'm not asking >>> > for an upgrade procedure, I'm familiar with that, but rather, how this >>> > change impacts the upgrade.) I think that the suggestion that the >>> > disks need to be reformatted is extreme and I hope something less >>> > extreme will suffice. > > > Just to point out the obvious, you shouldn't use "dangerous" and > "production" in the same sentence. :) > That depends on why "dangerous" was put into the name. In this case, it's a flag to indicate that we should understand what's going on underneath before using the feature in question. > >>> > Also, just to be clear, does this statement refer to boot disks, data >>> > disks, or both? >>> > >>> > It doesn't make sense to me that "dangerously dedicated" could have an >>> > impact on UFS filesystems specifically. A partition table is just a >>> > partition table, regardless of what filesystems might be written on >>> > disks, yes? Am I misunderstanding something here? >> >> I don't know why it would have an affect, but they say it does. > > > Did you see all the mailing list chatter about new installations > failing due to sysinstall not being able to newfs device names that > didn't exist? This is related. Also, a partition table isn't just a > partition table. It's a little more complex than that. It has > *nothing* to do with the filesystems inside. It has everything to do > with the way that FreeBSD looks at the drive to figure out what's on > it. See man pages for geom/gpart. There are others that have given a > better explanation than I can provide (marcus, juli). Search the > archives. Trust me, I didn't remove DD support from sysinstall just to > make life more complicated for everyone. I did this because as it > stands right now, it doesn't work. > > > It's not a filesystem thing. See above. > > -- randi > I think this is where the misunderstanding is. Based on what you said, the documentation should read "dangerously dedicated mode is no longer supported in sysinstall," is that correct? If we don't use sysinstall for anything, the change doesn't affect us. The current wording leads people to believe that something was changed in the FreeBSD geom internals that would, for example, prevent DD disks from being recognized in 8.0. As I read geom(4), there is nothing new in the tasting section about the way devices are offered to geom classes. - Max ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
> Did you see all the mailing list chatter about new installations > failing due to sysinstall not being able to newfs device names that > didn't exist? This is related. Also, a partition table isn't just a > partition table. It's a little more complex than that. It has > *nothing* to do with the filesystems inside. It has everything to do > with the way that FreeBSD looks at the drive to figure out what's on > it. See man pages for geom/gpart. There are others that have given a > better explanation than I can provide (marcus, juli). Search the > archives. Trust me, I didn't remove DD support from sysinstall just to > make life more complicated for everyone. I did this because as it > stands right now, it doesn't work. Sigh, correction. marcel, not marcus. -- randi ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
I'm going to just reply to all of these at once. On Tue, Dec 1, 2009 at 1:03 PM, Jerry McAllister wrote: > On Tue, Dec 01, 2009 at 07:59:42AM -0500, Maxim Khitrov wrote: > >> On Sat, Nov 28, 2009 at 12:28 PM, Peggy Wilkins wrote: >> > Due to history I won't go into, all my production (currently >> > 7.2-RELEASE) systems are installed onto "dangerously dedicated" disks. >> > What exactly do I need to do to upgrade them to 8.0? (I'm not asking >> > for an upgrade procedure, I'm familiar with that, but rather, how this >> > change impacts the upgrade.) I think that the suggestion that the >> > disks need to be reformatted is extreme and I hope something less >> > extreme will suffice. Just to point out the obvious, you shouldn't use "dangerous" and "production" in the same sentence. :) >> > Also, just to be clear, does this statement refer to boot disks, data >> > disks, or both? >> > >> > It doesn't make sense to me that "dangerously dedicated" could have an >> > impact on UFS filesystems specifically. A partition table is just a >> > partition table, regardless of what filesystems might be written on >> > disks, yes? Am I misunderstanding something here? > > I don't know why it would have an affect, but they say it does. Did you see all the mailing list chatter about new installations failing due to sysinstall not being able to newfs device names that didn't exist? This is related. Also, a partition table isn't just a partition table. It's a little more complex than that. It has *nothing* to do with the filesystems inside. It has everything to do with the way that FreeBSD looks at the drive to figure out what's on it. See man pages for geom/gpart. There are others that have given a better explanation than I can provide (marcus, juli). Search the archives. Trust me, I didn't remove DD support from sysinstall just to make life more complicated for everyone. I did this because as it stands right now, it doesn't work. > I take this to mean that any disk that is created without slice > and partition within slice needs to be redone. Probably it can all > be done in sysinstall, but you can do it with fdisk/bsdlabel/newfs. Or sade, although sade hasn't yet been updated to reflect the lack of DD support. Just don't use that option. > It does not matter if it is a boot disk or just a data disk. It > is whether or not it has a (one or more, up to 4) slice defined > and within the slice[s] partitions defined which are turned in to > filesystems. You can tell by the dev names in /etc/fstab. > > If they have the full device name /dev/da0s1a, ... da0s1h, they > are NOT dangerously dedicated and you should not have to worry. > > If the machine is dual booted with some MS thing as the other OS, then > it is very unlikely that they are dangerously dedicated. > > But, if they are like /dev/da0 or /dev/da0s1 (but with no 'a, b..h') > then they are dangerously dedicated and you need to convert them. What? No. 's1' refers to slice 1 (or partition 1, as you're referring to it). bsdlabel is used inside this slice to create a partition for each mount point (a,b,c, etc). See http://www.freebsd.org/doc/en/articles/formatting-media/x76.html. This documentation needs to be updated, but at least it'll give you a good explanation of how it used to work. With DD mode, you're creating a label against the drive itself, not a slice within. > First you would have to back up the contents of the disk, partition > by partition (mountable filesystem by mountable filesystem) however > you have it. Since it is 'dangerously dedicated' it is likely you > have a single filesystem per disk that needs backing up. > Check out that backup to make sure it is readable. There is no > going back. The backup can be done to tape or USB external disk > or network or any other media that will not be affected, has room > and can be written and read from the FreeBSD system. I think you're confusing running newfs against an unlabeled slice with DD mode. See above. DD mode means no slices, just a label for partitions. Not 'a single filesystem'. >> > >> > Thanks for helping to clear up my confusion... >> > >> > plw >> >> Peggy, >> >> Were you able to find an answer for this? I also have a number of >> servers and firewalls that use dangerously dedicated disks (boot and >> data). I don't see why UFS would care if it's mounted from ad1a vs. >> ad1s1a. It's not a filesystem thing. See above. -- randi ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Tue, Dec 01, 2009 at 07:59:42AM -0500, Maxim Khitrov wrote: > On Sat, Nov 28, 2009 at 12:28 PM, Peggy Wilkins wrote: > > Can someone elaborate on what exactly this statement in the 8.0 > > detailed release notes means? > > > > http://www.freebsd.org/releases/8.0R/relnotes-detailed.html#FS > > > >> 2.2.5 File Systems > >> > >> ???dangerously dedicated??? mode for the UFS file system is no longer > >> supported. > >> > >> Important: Such disks will need to be reformatted to work with this > >> release. > > > > Due to history I won't go into, all my production (currently > > 7.2-RELEASE) systems are installed onto "dangerously dedicated" disks. > > What exactly do I need to do to upgrade them to 8.0? (I'm not asking > > for an upgrade procedure, I'm familiar with that, but rather, how this > > change impacts the upgrade.) I think that the suggestion that the > > disks need to be reformatted is extreme and I hope something less > > extreme will suffice. > > > > Also, just to be clear, does this statement refer to boot disks, data > > disks, or both? > > > > It doesn't make sense to me that "dangerously dedicated" could have an > > impact on UFS filesystems specifically. A partition table is just a > > partition table, regardless of what filesystems might be written on > > disks, yes? Am I misunderstanding something here? I don't know why it would have an affect, but they say it does. I take this to mean that any disk that is created without slice and partition within slice needs to be redone.Probably it can all be done in sysinstall, but you can do it with fdisk/bsdlabel/newfs. It does not matter if it is a boot disk or just a data disk. It is whether or not it has a (one or more, up to 4) slice defined and within the slice[s] partitions defined which are turned in to filesystems. You can tell by the dev names in /etc/fstab. If they have the full device name /dev/da0s1a, ... da0s1h, they are NOT dangerously dedicated and you should not have to worry. If the machine is dual booted with some MS thing as the other OS, then it is very unlikely that they are dangerously dedicated. But, if they are like /dev/da0 or /dev/da0s1 (but with no 'a, b..h') then they are dangerously dedicated and you need to convert them. First you would have to back up the contents of the disk, partition by partition (mountable filesystem by mountable filesystem) however you have it. Since it is 'dangerously dedicated' it is likely you have a single filesystem per disk that needs backing up. Check out that backup to make sure it is readable. There is no going back. The backup can be done to tape or USB external disk or network or any other media that will not be affected, has room and can be written and read from the FreeBSD system. Then, boot a FreeBSD system that does not have the disk in question mounted. Probably you will need to use a 'fixit' image from the install CDs. Just for example, lets say, once your are booted, the disk to be converted shows up as /dev/ad1 and that it was all in one file system and that you want it to continue to be all in one file system. Do the following: (This makes a bootable drive and bootable partition with the standard FreeBSD MBR) (The dd-s just make sure old stuff is cleared) dd if=/dev/zero of=/dev/ad1 bs=512 count=1025 fdisk -BI ad1 dd if=/dev/zero of=/dev/ad1s1 bs=512 count=1025 bsdlabel -w -B ad1s1 bsdlabel -e ad1s1 The last bsdlabel command will bring up an edit screen. I suggest that you make at least some swap on this disk. So, you will want partition 'b' for swap and partition 'a' for everything else. Edit the partition label so it looks like: # /dev/ad0s3: 8 partitions: #size offsetfstype [fsize bsize bps/cpg] a: 8729532204.2BSD2048 16384 49160 b:** swap c: 898676100unused 0 0 # "raw" part, don't edit Those sizes are just an example. Use sizes that fit your disk. Using a * as the last size means it will use all remaining disk and the * in offset means it will calculate it properly. Of course, don't do anything to the 'c' line. Once that is done, newfs the partition to make a filesystem. newfs /dev/ad1s1a Note that fdisk and bsdlabel do not need the full path. They figure it out. But, the last I knew, newfs still does.Probably the defaults on newfs will work just fine. If you have huge numbers of tiny files you might want to adjust '-i' bytes per inode to increase number of inodes. You might also want to turn on softupdates with '-U'. jerry > > > > Thanks for hel
Re: 8.0-RELEASE and "dangerously dedicated" disks
On Sat, Nov 28, 2009 at 12:28 PM, Peggy Wilkins wrote: > Can someone elaborate on what exactly this statement in the 8.0 > detailed release notes means? > > http://www.freebsd.org/releases/8.0R/relnotes-detailed.html#FS > >> 2.2.5 File Systems >> >> “dangerously dedicated” mode for the UFS file system is no longer supported. >> >> Important: Such disks will need to be reformatted to work with this release. > > Due to history I won't go into, all my production (currently > 7.2-RELEASE) systems are installed onto "dangerously dedicated" disks. > What exactly do I need to do to upgrade them to 8.0? (I'm not asking > for an upgrade procedure, I'm familiar with that, but rather, how this > change impacts the upgrade.) I think that the suggestion that the > disks need to be reformatted is extreme and I hope something less > extreme will suffice. > > Also, just to be clear, does this statement refer to boot disks, data > disks, or both? > > It doesn't make sense to me that "dangerously dedicated" could have an > impact on UFS filesystems specifically. A partition table is just a > partition table, regardless of what filesystems might be written on > disks, yes? Am I misunderstanding something here? > > Thanks for helping to clear up my confusion... > > plw Peggy, Were you able to find an answer for this? I also have a number of servers and firewalls that use dangerously dedicated disks (boot and data). I don't see why UFS would care if it's mounted from ad1a vs. ad1s1a. - Max ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
8.0-RELEASE and "dangerously dedicated" disks
Can someone elaborate on what exactly this statement in the 8.0 detailed release notes means? http://www.freebsd.org/releases/8.0R/relnotes-detailed.html#FS > 2.2.5 File Systems > > “dangerously dedicated” mode for the UFS file system is no longer supported. > > Important: Such disks will need to be reformatted to work with this release. Due to history I won't go into, all my production (currently 7.2-RELEASE) systems are installed onto "dangerously dedicated" disks. What exactly do I need to do to upgrade them to 8.0? (I'm not asking for an upgrade procedure, I'm familiar with that, but rather, how this change impacts the upgrade.) I think that the suggestion that the disks need to be reformatted is extreme and I hope something less extreme will suffice. Also, just to be clear, does this statement refer to boot disks, data disks, or both? It doesn't make sense to me that "dangerously dedicated" could have an impact on UFS filesystems specifically. A partition table is just a partition table, regardless of what filesystems might be written on disks, yes? Am I misunderstanding something here? Thanks for helping to clear up my confusion... plw ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: slices to "dangerously dedicated"
On Tue, Jan 20, 2009 at 2:47 PM, Robert Huff wrote: > >Suppose I have a disk which was - for various reasons - lebeled > using slices. >Is it possible to change it to "dangerously dedicated" without > backup-wipe-relabel-restore cycle? > > >Robert Huff It is possible, but is probably a bad idea (it all depends on why you want to do this). I just ran a quick test in a virtual machine with a clean drive. The procedure was: # sysinstall (run the Fdisk tool to create a single s1 slice on /dev/da4) # bsdlabel -w /dev/da4s1 # newfs -U /dev/da4s1a # mount /dev/da4s1a /mnt # echo hello > /mnt/world # umount /mnt # fdisk (to find the starting block of s1) # sysctl kern.geom.debugflags=0x10 (may not be needed) # dd if=/dev/da4 of=/dev/da4 bs=16k skip=1 (might also want to specify 'count=' to limit the amount of data copied) # reboot After the reboot, I could mount /dev/da4a and read the original contents, s1 was no more. The key to getting it right is proper input positioning; you cannot do something like `dd if=/dev/da4s1 of=/dev/da4`. In my case, s1 started at block 32, so I set my dd block size to 16k and skipped the first block, placing me exactly at the start of s1 (512 * 32 = 16384 or 16k). You really don't want to copy one sector at a time (bs=512), and in my case, 16k is the highest that I could go. If you are moving some other slice like s2, you can set bs to 1 or 2 megs and just do proper calculation for what skip should be set to (bs * skip should equal 512 * staring block as reported by fdisk). Realize, however, that this isn't exactly the same as creating a "dangerously dedicated" disk from the start. You're just moving the first (or whatever slice you need) to the start of the drive along with any data that follows. You will not reclaim any disk space this way, though you may be able to use bsdlabel and growfs later to expand your partitions. Good luck! - Max P.S. Once again would like to emphasize that I would never do this on any real data because of the risks involved, but it was a fun exercise to try :) ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: slices to "dangerously dedicated"
using live CD/DVD make your new disklabel that mirrors existing but is in /dev/disk not /dev/diskslice, check it (try mount -r your partitions from /dev/disk[a-h]), clean MBR with fdisk, install bootrecord with bsdlabel -B /dev/disk then mount your / partition and fix etc/fstab it's not just about having few kB more space, but NOT having MS-partition table. for "religious" reason, for making thing simpler or less risky if you sometimes connect that drive to computer running windoze. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: slices to "dangerously dedicated"
On Tue, Jan 20, 2009 at 02:47:24PM -0500, Robert Huff wrote: > > Suppose I have a disk which was - for various reasons - lebeled > using slices. > Is it possible to change it to "dangerously dedicated" without > backup-wipe-relabel-restore cycle? > Not really.And why would you want to? Just leave it. You will gain nothing by the change. jerry > > Robert Huff > > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: slices to "dangerously dedicated"
On Jan 20, 2009, at 11:47 AM, Robert Huff wrote: Suppose I have a disk which was - for various reasons - lebeled using slices. Is it possible to change it to "dangerously dedicated" without backup-wipe-relabel-restore cycle? Nope. Since you'd only gain a megabyte of disk space (probably less) from the change, it's not worth bothering with, frankly... Regards, -- -Chuck ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
slices to "dangerously dedicated"
Suppose I have a disk which was - for various reasons - lebeled using slices. Is it possible to change it to "dangerously dedicated" without backup-wipe-relabel-restore cycle? Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: How do I re-format 'dangerously dedicated' drive?
On Sun, Nov 20, 2005 at 07:26:33PM -0500, Lowell Gilbert wrote: : Jonathon McKitrick <[EMAIL PROTECTED]> writes: : : > I don't have an MS-DOS floppy, and I think my CDROM isn't booting because the : > HD is 'dangerously dedicated,' even though it is a bootable CD and the BIOS is : > set to boot it first. : : That wouldn't be relevant. The BIOS is lying to you, or isn't capable : of booting this particular CD. I found that NetBSD doesn't boot from CD, FreeBSD 5.4 does, older DragonFly does not, but newer DFly does. I have no idea why, but my laptop doesn't like some CDROMs for booting. jm -- ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: How do I re-format 'dangerously dedicated' drive?
Just to make sure. You are using medias that your CD-ROM can read. I once almost ripped my hair of when I couldn't get an old machine to boot from cd. At the time I was using CD-RW medias and the drive was not able to read them. So if you are using CD-RW try a CD-R. Mats Hellman On 11/21/05, Jerry McAllister <[EMAIL PROTECTED]> wrote: > > > > > > > Hi all, > > > > I don't have an MS-DOS floppy, and I think my CDROM isn't booting > because the > > HD is 'dangerously dedicated,' even though it is a bootable CD and the > BIOS is > > set to boot it first. > > Since it is set to boot the HD first and it has a boot sector, the BIOS > doesn't want to get by that. > > So, you want to go in to the BIOS and reconfigure it to put the CD boot > in front of the HD. Then you can either completely reinstall the most > recent FreeBSD or use the fisit to rebuild something on that disk. > > The key thing is to have both floppy and CD in the boot order before > the Hard Disk. Change that only if you really need to. > > jerry > > > > > I want to totally clear my drive so I can reinstall from scratch from > CDROM. > > How can I do this? > > > > jm > > -- > > ___ > > freebsd-questions@freebsd.org mailing list > > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > > To unsubscribe, send any mail to " > [EMAIL PROTECTED]" > > > > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to " > [EMAIL PROTECTED]" > ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: How do I re-format 'dangerously dedicated' drive?
> > > Hi all, > > I don't have an MS-DOS floppy, and I think my CDROM isn't booting because the > HD is 'dangerously dedicated,' even though it is a bootable CD and the BIOS is > set to boot it first. Since it is set to boot the HD first and it has a boot sector, the BIOS doesn't want to get by that. So, you want to go in to the BIOS and reconfigure it to put the CD boot in front of the HD. Then you can either completely reinstall the most recent FreeBSD or use the fisit to rebuild something on that disk. The key thing is to have both floppy and CD in the boot order before the Hard Disk. Change that only if you really need to. jerry > > I want to totally clear my drive so I can reinstall from scratch from CDROM. > How can I do this? > > jm > -- > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "[EMAIL PROTECTED]" > ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: How do I re-format 'dangerously dedicated' drive?
Jonathon McKitrick <[EMAIL PROTECTED]> writes: > I don't have an MS-DOS floppy, and I think my CDROM isn't booting because the > HD is 'dangerously dedicated,' even though it is a bootable CD and the BIOS is > set to boot it first. That wouldn't be relevant. The BIOS is lying to you, or isn't capable of booting this particular CD. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: How do I re-format 'dangerously dedicated' drive?
On Sun, 2005-11-20 at 23:24 +, Jonathon McKitrick wrote: > Hi all, > > I don't have an MS-DOS floppy, and I think my CDROM isn't booting because the > HD is 'dangerously dedicated,' even though it is a bootable CD and the BIOS is > set to boot it first. > > I want to totally clear my drive so I can reinstall from scratch from CDROM. > How can I do this? > > jm I would reset the BIOS to boot from the CD, and then do a complete reinstall. The boot order can usually be set to whatever you like. A complete reinstall will then give you the opportunity to restore the usual disk labels and boot manager. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
How do I re-format 'dangerously dedicated' drive?
Hi all, I don't have an MS-DOS floppy, and I think my CDROM isn't booting because the HD is 'dangerously dedicated,' even though it is a bootable CD and the BIOS is set to boot it first. I want to totally clear my drive so I can reinstall from scratch from CDROM. How can I do this? jm -- ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: Dangerously dedicated vs. fully dedicated, etc.
In <[EMAIL PROTECTED]>, Ian Dowse <[EMAIL PROTECTED]> typed: > In message <[EMAIL PROTECTED]>, [EMAIL PROTECTED] writes: > >Mike, I'll pay back your effort in replying to this long thing by > >working up a patch for the "disklabel" manpage (at least) and, if you > >want, I'll CC you so you can veto things you don't like. I do worry > (B) Dedicated format created by sysinstall > > > > sector 0: boot1 and the DOS slice table, where > the slice table contains one slice > (slice 1) covering the entire disk, > including sector 0. > sector 1: disklabel > sector 2-15:boot2 > sectors 16-31: 'a' partition filesystem superblock > > In this case, there is no boot0, and boot1 serves as the boot > loader that is invoked by the BIOS. Here, all of the boot code > is contained within the first slice and also within the first > partition. Again, the 8k reserved at the start of every ffs > filesystem protects the boot code. Sysinstall sets up fstab to > refer to the partitions as e.g. /dev/ad0s1a (I think). This can also be referred to as /dev/ad0a, like your C case. I personally prefer that because it lets you know that the disk is DD. http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information. ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: Dangerously dedicated vs. fully dedicated, etc.
In <[EMAIL PROTECTED]>, Ian Dowse <[EMAIL PROTECTED]> typed: > As to the issue of BIOSes disliking DD modes, there have been a few > different reasons suggested. I had a dual xeon BIOS that had "anti-virus" code. If the boot block didn't have the write MBR on it, it rewrote the first 63 sectors, clobbering my DD (type B) disklabel. It could be turned off in the BIOS, but caused me (not the kernel) to panic the first time it happened. http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information. ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: Dangerously dedicated vs. fully dedicated, etc.
Mike Meyer <[EMAIL PROTECTED]> writes: > As you can see, it's sector 1, not sector 0. Everything else seems to > be correct. More terminology problems. "1" means "0". Says "fdisk": Warning: BIOS sector numbering starts with sector 1 To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message
Re: Dangerously dedicated vs. fully dedicated, etc.
In <[EMAIL PROTECTED]>, Gary W. Swearingen <[EMAIL PROTECTED]> typed: > Ian Dowse <[EMAIL PROTECTED]> writes: > You've cleared up several things, thanks. (I still don't see why any > BIOS would have trouble with a DD disk, leading to DD's deprecation, but > I can just take people's word for it, for the task at hand.) BTW, I've > seen both of your options referred to as DD, if I understood it right. There are BIOSes out there that check sector 0, and fail to recognize the disk if it if the MBR doesn't conform to their idea of "valid". Some of them will overwite sector 0 with a "valid" MBR in that case. I've had this happen to me, meaning my disk was fried every time I rebooted the system - until I turned off the "Virus protection" feature of the BIOS. > > (C) Dedicated format using dummy slice > ... > One such as would be created by "disklabel -B". (/boot/boot1 seems to > have the fourth slice pre-defined.) This differs from "B" only in the > slice table, right? The "disklabel" manpage implies that this is a DD. Yes, the slice table is the only difference. This is what you get if you install a "dangerously dedicated" disk with the i386 installer. In fact, I've got one here: Information from DOS bootblock is: The data for partition 1 is: sysid 165,(FreeBSD/NetBSD/386BSD) start 0, size 17942584 (8761 Meg), flag 80 (active) beg: cyl 0/ head 0/ sector 1; end: cyl 1023/ head 17/ sector 4 The data for partition 2 is: The data for partition 3 is: The data for partition 4 is: > It seems that a DD disk is one which is similar to a single slice > starting at sector 0, regardless of what the slice table part of sector > 0 contains. With FreeBSD-standard boot code and some BIOSes, one disk > layout (ie, DD or sliced) will work better than the other. (And for DD > disks, some slice table contents might work better than others. I've > not read anything comparing your "B" and "C" or either with a slice > table full of zeros or random bits.) As you can see, it's sector 1, not sector 0. Everything else seems to be correct. http://www.mired.org/consulting.html Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message
Re: Dangerously dedicated vs. fully dedicated, etc.
In <[EMAIL PROTECTED]>, Gary W. Swearingen <[EMAIL PROTECTED]> typed: > Mike, I'll pay back your effort in replying to this long thing by > working up a patch for the "disklabel" manpage (at least) and, if you > want, I'll CC you so you can veto things you don't like. I do worry > about how so few people comment on manpage changes before they go in, > but they need improvement so badly it's worth the risk of a few errors. > If you can't reply or even read it, that's OK too; I think I learned > something in the writing of it. I'd be more than happy to review any changes you make. And I'm happy to see you turning things into something more substantial than an archived message. http://www.mired.org/consulting.html Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message
Re: Dangerously dedicated vs. fully dedicated, etc.
In message <[EMAIL PROTECTED]>, [EMAIL PROTECTED] writes: >/boot/boot0 has the FreeBSD bootloader. The installer also offers >to use the "standard" /boot/mbr. >Roughly speaking. /boot/boot2 is 15 sectors; I suppose the first >(all zeros) is replaced with the disklabel, loosely speaking. >One such as would be created by "disklabel -B". (/boot/boot1 seems to >have the fourth slice pre-defined.) This differs from "B" only in the >slice table, right? The "disklabel" manpage implies that this is a DD. Exactly. Thanks for filling in the details I missed. The other magic thing about the bogus 5-sector slice is that the kernel detects this special case and then completely ignores the slice table and makes the compatibility slice cover the whole disk (I'm not 100% sure of the details here). >It seems that a DD disk is one which is similar to a single slice >starting at sector 0, regardless of what the slice table part of sector >0 contains. With FreeBSD-standard boot code and some BIOSes, one disk >layout (ie, DD or sliced) will work better than the other. (And for DD >disks, some slice table contents might work better than others. I've >not read anything comparing your "B" and "C" or either with a slice >table full of zeros or random bits.) I think to avoid warnings or errors, you need either a valid slice entry (even if it is a sysinstall-style slice that starts at sector 0 and contains the whole disk), or else the exact special bogus slice table, since the kernel code just does a bcmp() to check for the special bogus table. As to the issue of BIOSes disliking DD modes, there have been a few different reasons suggested. For traditional BIOSes that just look for the 0x55 0xaa signature and if found then execute the MBR code, all of the various DD and non-DD schemes should work fine. However, some BIOSes perform additional tests that may fail on DD disks. For example (I'm just guessing here), they might check that the slice starts after the MBR, or that the slice starts and ends on a cylinder boundary. It sounds a silly thing to do, but I guess maybe it allows the BIOS to automatically figure out what geometry the OS is expecting or something. The fact that boot1 always contains the bogus slice table even when boot1 is not used as an MBR has been linked to other BIOS problems too - some BIOSes apparently go further and check if the first sector of each slice looks like it has an extended partition table even if the slice type is not that of an extended partition. In -CURRENT, the default bogus slice table was changed slightly to stop some BIOSes crashing with a divide-by-zero error when they tried to parse the bogus slice entry in boot1. Ian To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message
Re: Dangerously dedicated vs. fully dedicated, etc.
Ian Dowse <[EMAIL PROTECTED]> writes: > At the risk of adding to the confusion, here is a less wordy > description of the various disk layouts. The term `dangerously > dedicated' seems to be used to refer to either options (B) or (C), > so I will avoid using that term: You've cleared up several things, thanks. (I still don't see why any BIOS would have trouble with a DD disk, leading to DD's deprecation, but I can just take people's word for it, for the task at hand.) BTW, I've seen both of your options referred to as DD, if I understood it right. > (A) Normal sliced disk (assuming sectors/track = 63) > > sector 0: boot0 and the DOS slice table /boot/boot0 has the FreeBSD bootloader. The installer also offers to use the "standard" /boot/mbr. > > (B) Dedicated format created by sysinstall ... > sector 1: disklabel > sector 2-15:boot2 Roughly speaking. /boot/boot2 is 15 sectors; I suppose the first (all zeros) is replaced with the disklabel, loosely speaking. The installer (and its code) calls this a DD disk. > (C) Dedicated format using dummy slice ... One such as would be created by "disklabel -B". (/boot/boot1 seems to have the fourth slice pre-defined.) This differs from "B" only in the slice table, right? The "disklabel" manpage implies that this is a DD. It seems that a DD disk is one which is similar to a single slice starting at sector 0, regardless of what the slice table part of sector 0 contains. With FreeBSD-standard boot code and some BIOSes, one disk layout (ie, DD or sliced) will work better than the other. (And for DD disks, some slice table contents might work better than others. I've not read anything comparing your "B" and "C" or either with a slice table full of zeros or random bits.) Thanks again. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message
Re: Dangerously dedicated vs. fully dedicated, etc.
In message <[EMAIL PROTECTED]>, [EMAIL PROTECTED] writes: >Mike, I'll pay back your effort in replying to this long thing by >working up a patch for the "disklabel" manpage (at least) and, if you >want, I'll CC you so you can veto things you don't like. I do worry At the risk of adding to the confusion, here is a less wordy description of the various disk layouts. The term `dangerously dedicated' seems to be used to refer to either options (B) or (C), so I will avoid using that term: (A) Normal sliced disk (assuming sectors/track = 63) sector 0: boot0 and the DOS slice table sectors 1..62:unused sector 63:boot1 sector 64:disklabel sectors 65-78:boot2 sectors 79-92:'a' partition filesystem superblock Note that the disklabel, which contains a list of the partitions within a slice is actually contained within the space allocated to the first partition. To ensure that this does not get clobbered by the filesystem, the first 8k of every ffs filesystem is reserved for boot code and the disklabel. (B) Dedicated format created by sysinstall sector 0: boot1 and the DOS slice table, where the slice table contains one slice (slice 1) covering the entire disk, including sector 0. sector 1: disklabel sector 2-15: boot2 sectors 16-31:'a' partition filesystem superblock In this case, there is no boot0, and boot1 serves as the boot loader that is invoked by the BIOS. Here, all of the boot code is contained within the first slice and also within the first partition. Again, the 8k reserved at the start of every ffs filesystem protects the boot code. Sysinstall sets up fstab to refer to the partitions as e.g. /dev/ad0s1a (I think). (C) Dedicated format using dummy slice sector 0: boot1 and the DOS slice table. The slice table contains a single entry (slice 4) that starts at sector 0 and has a size of 5 sectors, whatever the real disk size is. sector 1: disklabel sector 2-15: boot2 sectors 16-31:'a' partition filesystem superblock This is like (B) except that slice 4 instead of slice 1 is used, and the size of the slice in the slice table is bogus. The partitions on such a disk are usually accessed using the compatibility slice names such as /dev/ad0a. Ian To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message
Re: Dangerously dedicated vs. fully dedicated, etc.
Mike, I'll pay back your effort in replying to this long thing by working up a patch for the "disklabel" manpage (at least) and, if you want, I'll CC you so you can veto things you don't like. I do worry about how so few people comment on manpage changes before they go in, but they need improvement so badly it's worth the risk of a few errors. If you can't reply or even read it, that's OK too; I think I learned something in the writing of it. Mike Meyer <[EMAIL PROTECTED]> writes: > In <[EMAIL PROTECTED]>, Gary W. Swearingen <[EMAIL PROTECTED]> >typed: > > I'm having trouble understanding a couple parts of the "disklabel" > > manpage related to dangerously/fully dedicated disks. > > > > The "BUGS" section has this paragraph: > > > > For the i386 architecture, the primary bootstrap sector contains an > > embedded fdisk table. The disklabel utility takes care to not > > clobber it when installing a bootstrap only (-B), or when editing an > > existing label (-e), but it unconditionally writes the primary > > bootstrap program onto the disk for -w or -R, thus replacing the > > fdisk table by the dummy one in the bootstrap program. This is only > > of concern if the disk is fully dedicated, so that the BSD disklabel > > starts at absolute block 0 on the disk. > > > > 1) Can anyone explain that last sentence to me? Shouldn't that "is only > > of concern" instead be "is not of concern", reversing the sense? > > No, it's right. But you say that a fully dedicated disk has a standard disklabel. So the fdisk table is the dummy one, by definition of "standard". So why would replacing it with another dummy one concern me (as the quote says it should)? I now suspect that "fully" means "dedicated", and I should be concerned that it's fake fdisk table not get overwritten (but I don't see why it even needs a fake table -- more below). And if I have normally sliced disk, whouldn't I also be concerned if "disklabel" was going to "replace the fdisk table" when it "writes the primary bootstrap program"? That depends on definitions. I was confused by FreeBSD referring to boot1 as the "primary bootstrap" while it seems so obvious that boot0 (MBR) is the primary bootstrap. The about manpage quote seemed to imply that the MBR's "fdisk table" could be overwritten; made even more wrong because there is no other fdisk table, really. The boot1 dummy table is not an "fdisk table" because fdisk knows nothing about it on a sliced disk. I think "only of concern if" should be "only true if". I think there's a terminology mess here. Looking further, I see that my filesystem has a block size of 16384, but disklabel.c seems to use a "boot block" size of 8192 (presumably to fit in /boot/boot1 (512) and /boot/boot2 (7680, part of which is a placeholder for the disklabel sector); which the code refers to as "block 0" and "block 1-15"! > > 2) Is a "fully dedicated" disk exactly the same as a "dangerously > > dedicated" disk? If not, what's the difference? Can one use a disk > > (or a slice) which has no space reserved for stage 1 & 2 boot records, > > say, for a non-bootable disk? I know no way to disklabel one that way. > > I've never seen "fully dedicated" anywhere else, so I can't say for > sure. However, I suspect they are using that to distinguish a drive on > a non-PC system - which has a standard disklabel in block 0 - from a > dangerously dedicated drive, which has a dangerously dedicated > disklabel in block 0. So then what's the difference between "a standard disklabel" and "a dangerously dedicated disklabel"? Is it only that the std one has a dummy partition table and the DD one has a "fake" table, where "dummy" means "whatever is in boot1 (some warning text?)" and "fake" means "some data as if the disk was sliced"? (More below.) > > 3) Is "block 0" exactly the same as "sector 0"? > > No. Block 0 is a file system block, whose size depends on the > parameters you gave newfs when you created the file system. I've seen > reports that booting won't work if you don't use the default values on > the root file system, but have never verified them. Sector 0 is the > first sector of block 0. It looked to me like disklabel.c is using 8192, regardless of FS params. I don't know why my root FS has 16384 since it's less than 1 GB so it's supposed to be 8192. But it
Re: Dangerously dedicated vs. fully dedicated, etc.
In <[EMAIL PROTECTED]>, Gary W. Swearingen <[EMAIL PROTECTED]> typed: > I'm having trouble understanding a couple parts of the "disklabel" > manpage related to dangerously/fully dedicated disks. > > The "BUGS" section has this paragraph: > > For the i386 architecture, the primary bootstrap sector contains an > embedded fdisk table. The disklabel utility takes care to not > clobber it when installing a bootstrap only (-B), or when editing an > existing label (-e), but it unconditionally writes the primary > bootstrap program onto the disk for -w or -R, thus replacing the > fdisk table by the dummy one in the bootstrap program. This is only > of concern if the disk is fully dedicated, so that the BSD disklabel > starts at absolute block 0 on the disk. > > 1) Can anyone explain that last sentence to me? Shouldn't that "is only > of concern" instead be "is not of concern", reversing the sense? No, it's right. > 2) Is a "fully dedicated" disk exactly the same as a "dangerously > dedicated" disk? If not, what's the difference? Can one use a disk > (or a slice) which has no space reserved for stage 1 & 2 boot records, > say, for a non-bootable disk? I know no way to disklabel one that way. I've never seen "fully dedicated" anywhere else, so I can't say for sure. However, I suspect they are using that to distinguish a drive on a non-PC system - which has a standard disklabel in block 0 - from a dangerously dedicated drive, which has a dangerously dedicated disklabel in block 0. > 3) Is "block 0" exactly the same as "sector 0"? No. Block 0 is a file system block, whose size depends on the parameters you gave newfs when you created the file system. I've seen reports that booting won't work if you don't use the default values on the root file system, but have never verified them. Sector 0 is the first sector of block 0. > 4) Shouldn't "BSD disklabel starts at absolute block 0" be "FreeBSD > stage 1 boot record starts at sector 0"? The disklabel immediately > follows the stage 1 boot record, right? So it would be "block 1"? No, both the stage 1 boot and the disklabel are in block 0. > Under "Writing a standard label", the manpage says: > > PC-based systems have special requirements in order for the BIOS to > properly recognize a FreeBSD disklabel. Older systems may require > what is known as a ''dangerously dedicated'' disklabel, which > creates a fake DOS partition to work around problems older BIOSes > have with modern disk geometries. > > 5) What's "fake DOS partition"? DD disks don't have partitions. Is it > just trying to not bother saying that it fills in the MBR partition > table as if there was at least one slice which the DD MBR will ignore. DD disks don't have fdisk partitions, but they have an fdisk table. It has one partition that covers the entire disk. That's probably what they are referring to. Note that the system also supports accessing the drive as if it had one fdisk partition, so that da0s1a and da0a reference the same bit of disk if da0 is DD. > 6) Why is the problem limited to older systems? Don't new BIOSes > check for a normal-looking partition table? The BIOS checking the fdisk table isn't what you're avoiding with a DD disk. What you're avoiding is the BIOS geometry calculations at boot time. Older BIOSes apparently have trouble with that. > 7) Isn't the first sentence wrong? BIOS don't look for disklabels, do > they? The special requirements are in order for the BIOS to find the > FreeBSD stage 1 boot record, no?. (And the FreeBSD installer doesn't > satisfy the requirements for non-DD disks (as I read the FAQ's DD > answer). I can't imagine why not. Older systems with a standard > MBR boot any active slice (even FreeBSD) without problems, no?) I think the first sentence has confusing wording, in that PC BIOSes could be confused if there wasn't an fdisk table. It should say "recognize disks with a FreeBSD disklabel." A standard FreeBSD disklabel does *not* have an fdisk table in it. That's what gets put at the beginning of fdisk partitions, and at the beginning of disks on non-PC based systems. If you put that at the beginning of a disk on a PC, you could confuse the BIOS. The special requirements are that you have an fdisk table. On non-DD disks, the FreeBSD installer installs either a standard MBR or a boot0 MBR, both of which have an fdisk table. It then installs standard disk labels on the fdisk partitions, where they won't confuse anything. http://www.mired.org/consulting.html Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message
Dangerously dedicated vs. fully dedicated, etc.
I'm having trouble understanding a couple parts of the "disklabel" manpage related to dangerously/fully dedicated disks. The "BUGS" section has this paragraph: For the i386 architecture, the primary bootstrap sector contains an embedded fdisk table. The disklabel utility takes care to not clobber it when installing a bootstrap only (-B), or when editing an existing label (-e), but it unconditionally writes the primary bootstrap program onto the disk for -w or -R, thus replacing the fdisk table by the dummy one in the bootstrap program. This is only of concern if the disk is fully dedicated, so that the BSD disklabel starts at absolute block 0 on the disk. 1) Can anyone explain that last sentence to me? Shouldn't that "is only of concern" instead be "is not of concern", reversing the sense? 2) Is a "fully dedicated" disk exactly the same as a "dangerously dedicated" disk? If not, what's the difference? Can one use a disk (or a slice) which has no space reserved for stage 1 & 2 boot records, say, for a non-bootable disk? I know no way to disklabel one that way. 3) Is "block 0" exactly the same as "sector 0"? 4) Shouldn't "BSD disklabel starts at absolute block 0" be "FreeBSD stage 1 boot record starts at sector 0"? The disklabel immediately follows the stage 1 boot record, right? So it would be "block 1"? Under "Writing a standard label", the manpage says: PC-based systems have special requirements in order for the BIOS to properly recognize a FreeBSD disklabel. Older systems may require what is known as a ''dangerously dedicated'' disklabel, which creates a fake DOS partition to work around problems older BIOSes have with modern disk geometries. 5) What's "fake DOS partition"? DD disks don't have partitions. Is it just trying to not bother saying that it fills in the MBR partition table as if there was at least one slice which the DD MBR will ignore. 6) Why is the problem limited to older systems? Don't new BIOSes check for a normal-looking partition table? 7) Isn't the first sentence wrong? BIOS don't look for disklabels, do they? The special requirements are in order for the BIOS to find the FreeBSD stage 1 boot record, no?. (And the FreeBSD installer doesn't satisfy the requirements for non-DD disks (as I read the FAQ's DD answer). I can't imagine why not. Older systems with a standard MBR boot any active slice (even FreeBSD) without problems, no?) To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message
